Soda Ash Titration

Abstract: During this experiment, the percent sodium oxide was determined by titrating unknown 10, a soda ash sample, with 0.1M hydrochloric acid and using the pH and indicators to determine the double endpoints of the reaction taking place. Also the first and second derivatives were used to better determine where the end points were on the graph. The results of this experiment were deemed inconclusive due to a lack of understanding of the process of determining the end point from the graphs and how to properly determine the percent sodium oxide in the soda ash sample. This experiment did emphasized important concepts in volumetric titration, significant figures and data treatment even though a final result was not determined.

1.0 Introduction

During the following experiment, a volumetric titration was performed to determine the percent Na2O in an unknown soda ash sample. Several important techniques discussed here were used to determine the desired data. These techniques included; pH electrode calibration, preparation of water for use in making solutions, dilution, standardization of the 0.1M HCl, weighing, graphing, and titration. During the first portion of the experiment, two liters of water was boiled to drive off the carbon dioxide which was present through atmospheric absorption. This was a vital step in ensuring that pure water was added to the weighed out masses of sodium carbonate and the unknown 10. This concept is equally important when looking at chemicals or compounds to be used as a primary standard or reagent. A primary standard is a reagent that is pure enough and stable enough to be used directly after weighing.1The primary standards are also resistant to reaction with the atmosphere and have a large molar mass.2 The primary standard used in this experiment was sodium carbonate which was used in the standardization of the 0.1M HCl. Before the standardization technique was used, the pH electrode/meter had to be properly...